SCID Is Defined by a Lack of Functional B and T

question 65

Multiple Choice

SCID is defined by a lack of functional B and T cells which eliminates protection by humoral and cell-mediated immunity. Which of the following is true?

• A) A genetic defect disrupts the development of the lymphocytic cell lines.
• B) A genetic mutation renders the individual incapable of removing a toxic DNA metabolite from lymphocytes, which ultimately destroys them.
• C) Genes coding for B and T cell receptors are mutated so the cells are incapable of binding antigens.
• D) Genes that code for interleukin receptors are mutated so the individual's B and T cells do not receive the activation signals, rendering them useless.
• E) All of the choices describe cases of SCID.

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Definitions:

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Opportunity Cost

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Quantity of laundry being washed and dried in a single operation or cycle.